Marcos Efraín Masís Fernández (San Juan, August 9, 1989), known professionally as Tainy, is a Puerto Rican music producer, composer, and DJ.

He rose to prominence in the genre, collaborating on the production of Mas Flow 2 at the age of fifteen, and later working with Luny Tunes on the album Mas Flow: Los Benjamins at the age of seventeen. In a 2021 Billboard list, he was included among the top ten producers of the 21st century.

In an interview, Tainy stated that his career can be defined by three pivotal moments, starting with the success of Daddy Yankee's album Barrio Fino, which motivated him to produce songs and allowed him to meet the duo Wisin & Yandel; while the other cases occurred during his work with J Balvin (Vibras) and Bad Bunny (X100pre), where he was able to experiment and participate more in the composition, using guitars and synth-pop tracks. In other interviews he stated that the opportunities given in albums like Más Flow 2 and Pa'l Mundo helped him "put his name on the map." Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.